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arXiv · 2509.18247

SU(4) Kondo Lattice in Semiconductor Moir\'e Materials

Sunghoon Kim
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Abstract

Motivated by recent advances in transition metal dichalcogenide (TMD) moir\'e materials, we propose TMD moir\'e multilayers as a platform for realizing an approximately SU(4)-symmetric triangular Kondo lattice, generalizing the concept of the double quantum dot model. Our model extends the conventional Kondo lattice by incorporating a three-site exchange of SU(4) local moments, which drives spontaneous time-reversal and lattice symmetry breaking. Using a parton mean-field approach, we map out the phase diagram as a function of three-site exchange and hole doping. In the Kondo-unscreened regime, we identify Mott insulating phases, including bond-ordered states and a chiral spin liquid. With increasing doping, Kondo hybridization gives rise to a heavy Fermi liquid that exhibits distinct patterns of lattice symmetry breaking, with or without topological responses. We conclude with directions for future study.

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Sunghoon Kim. 2025-09-22. SU(4) Kondo Lattice in Semiconductor Moir\'e Materials. https://doi.org/10.1103/jnjq-clrk

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